Effects of redox mediators on Α-Fe₂O₃ exposed by {012} and {104} facets for photocatalytic water oxidation

The mechanism study of redox mediator to transfer the photogenerated electrons is extremely desirable for artificial Z-scheme photocatalytic systems. Here we find that the α-Fe₂O₃exposed by {012} and {104} facets can facilitate the reduction of IO₃⁻, which results in increasing the activity of photocatalytic water oxidation significantly. By employing NaIO₃as an electron acceptor, the O₂evolution activity (309.4 μmol h⁻¹ g⁻¹) of α-Fe₂O₃photocatalyst mainly exposed by {012} and {104} facets is 84 times higher than that (3.68 μmol h⁻¹ g⁻¹) of α-Fe₂O₃mostly exposed by {101} and {111} planes. We anticipate that the findings in this work may open the door for further development of enhanced Z-scheme photocatalytic systems.